"Earthquake-Proof?" - Towards Resilient and Economical Steel Building Systems

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Many owners expect new buildings to be "earthquake-proof," defined in this proposal as an ideal of perfect seismic resilience (zero failure probability and consequences, zero time to recovery). Conversely, most current seismic design is based on allowing damage to selected "ductile" parts of a structure, resulting in performance that is far from "earthquake-proof." This difference between the expectations of engineers and of the public was highlighted by the 2010-2011 earthquakes near Christchurch, New Zealand, which led to the demolition of over one thousand buildings. In Canada, a single large earthquake is expected to cause over $60 billion in losses, several times more devastating than the costliest natural disaster in Canadian history. In smaller but more frequent earthquakes, losses are likely to be dominated by damage to Operational and Functional Components (OFCs, i.e. non-structural elements such as cladding and mechanical equipment) that are only minimally considered in typical design. The socioeconomic impact of these earthquakes would be felt not only through direct repair costs, but also indirect losses like downtime during repair. Even if completely "earthquake-proof" construction may not be attainable, there is still a clear need to move towards the more seismically resilient construction that the public expects, while still minimizing construction costs. To this end, the objectives of Focus Area A include validating Canadian design guidelines for Controlled Rocking Braced Frames (CRBFs), both coupled with the gravity framing system (G-CRBFs) and separated from it, so that they can be considered for inclusion in the National Building Code and CSA Standard S16 (Design of Steel Structures). In Focus Area B, the objectives include validating design provisions for "strongback braced frames" with Replaceable Brace Modules (RBMs) recently developed by the applicant. Finally, recognizing that seismically resilient construction will require both structural systems that can be quickly repaired and OFCs that can withstand the demands they experience, Focus Area C will use Artificial Intelligence to optimize the seismic design of steel building systems within a Performance-Based Earthquake Engineering framework, with an objective of providing guidance on how to design to minimize total seismic losses. The long-term vision of this research program is for seismic resilience to become a routine objective for all engineered structures in Canada, rather than an enhanced objective reserved for exceptional structures. Building on the applicant's demonstrated leadership in earthquake engineering for enhanced seismic resilience of steel building systems, the proposed research will have direct benefits for Canada by providing guidance to reduce the socioeconomic cost of earthquakes, while providing an inclusive environment for training Highly Qualified Personnel (HQP) to lead the field towards more seismically resilient and economical structures.